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In this paper, a 1:21 model experiment was conducted to discuss the dust diffusion efficiency and liner trolley obstruction effect inside the tunnel at - 9% to 9%, the effect of different initial dust concentrations on dust diffusion and liner trolley obstruction effect at 6% slope, and the effect of different return air velocity on dust diffusion at 6% slope, the reliability of the results is verified by computational fluid dynamics simulations. The results show that as the slope of the tunnel changes from 0 to - 9%, the average dust diffusion time decreases by 3.7% at the working face and the dust concentration difference between the front and rear of the trolley is improved by 2.7%. When the slope of the tunnel changes from 0 to - 9%, the average dust diffusion time increases by 7.2% at the working face and the dust concentration difference between the front and rear of the trolley is improved by 17.9%. With each 100 mg/m increase in the initial dust concentration, the dust diffusion time at the working face and the tunnel exit increases by 9.15% and 8.17% on average, and the lining trolley obstruction time increases by 23.33 s on average. The dust diffusion times take an average reduction rate of 15.7%, with the increase of return air velocity. The recommended return air velocity is greater than 1 m/s for large slope tunnels. When the slope changes from 0° to 9°, the hindrance rate of slope on dust diffusion is 2.88462%, 8.65385%, and 16.34615% respectively. Dust diffusion efficiency will be reduced as the tunnel slope changes from 0° to 9°, The growth rate of slope on dust diffusion is - 0.96154%, - 2.88462%, and - 6.73077% respectively.
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http://dx.doi.org/10.1038/s41598-023-46242-5 | DOI Listing |
J Mol Model
August 2025
State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization, Henan Polytechnic University, Jiaozuo, 454003, China.
Context: In coal mine spray dust suppression, conventional studies on individual surfactants or surfactant mixtures often fail to achieve optimal coal wettability enhancement. This study innovatively introduces SiO₂ nanoparticles and demonstrates through simulations that the nanoparticle-surfactant composite system substantially enhances coal wettability. Electrostatic potential analysis indicates that the modified nanoparticle molecules formed by surfactant-grafted nanoparticles are more likely to form stable structures with coal molecules, enabling the nanoparticles to be better fixed on the coal molecules and establish a stable adsorption configuration.
View Article and Find Full Text PDFOpen Res Eur
May 2025
Rosseland Centre for Solar Physics, Universitetet i Oslo, Oslo, N-0315, Norway.
Understanding the physical processes that regulate star formation and galaxy evolution are major areas of activity in modern astrophysics. Nearby galaxies offer unique opportunities to inspect interstellar medium (ISM), star formation (SF), radiative, dynamic and magnetic ( ) physics in great detail from sub-galactic (kpc) scales to sub-cloud (sub-pc) scales, from quiescent galaxies to starbursts, and from field galaxies to overdensities. In this case study, we discuss the major breakthroughs in this area of research that will be enabled by the Atacama Large Aperture Submillimeter Telescope (AtLAST), a proposed 50-m single-dish submillimeter telescope.
View Article and Find Full Text PDFNat Commun
July 2025
School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA.
Chondrules are a characteristic feature of primitive Solar System materials and are common in all primitive meteorites except the CI-chondrites. They are thought to form owing to melting of solid dust aggregates by energetic processing within the solar nebula and thus record fundamental processes within protoplanetary disks. We report the discovery of abundant altered microchondrules (>350 ppm) with modal sizes of 6-8 µm within sample A0180 from C-type asteroid Ryugu.
View Article and Find Full Text PDFUltrason Sonochem
September 2025
State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization, School of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 Yunnan, China; School of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kun
A novel ultrasonic-enhanced hydrogen peroxide leaching method is proposed for efficient cadmium recovery from flue dust under room temperature and neutral conditions, addressing the limitations of conventional methods such as low efficiency and environmental pollution. Under optimal conditions (room temperature, 5 mL HO, 2:1 liquid-solid ratio, 20 min, and 360 W ultrasonic power), the cadmium leaching efficiency reaches 96.76 %, significantly higher than the conventional oxidative leaching efficiency of 88.
View Article and Find Full Text PDFJ Oral Sci
July 2025
Department of Pedodontics and Preventive Dentistry, Faculty of Dentistry, Srinakharinwirot University.
Purpose: This study investigated effectiveness of a silicone mask fitter for reduction of composite particle leakage during removal of bonded attachments for clear aligners compared with a surgical mask and an N95 respirator.
Methods: Composite particles passing through masks were measured using a particle counter machine during removal of attachments bonded on a dentoform using a slow-speed handpiece. The samples were: Group 1: a surgical mask; Group 2: a surgical mask with a silicone mask fitter; and Group 3: an N95 respirator.